The purpose
of this guide

Is writing
important in chemistry? Don’t chemists spend their time turning knobs, mixing
reagents, and collecting data? They still get to do those things, but
professional scientists also make presentations, prepare reports, publish results, and submit
proposals. Each of these activities involves writing. If you remain skeptical
about the need for writing skills, then ask your favorite professor, or any
other scientist, to track the fraction of one workday spent using their word
processing program. You (and they) may be surprised at the answer

Although the exchange of information in science usually focuses on content rather than
writing style, it is important that work be presented using accepted conventions
and in an appropriate syle.
Whether your audience consists of readers, reviewers, seminar attendees, or the
boss, a clear, concise writing style can help to gain their confidence,
maintain their interest, and convince them of your work’s value. In a
competitive environment, this can be an important part of having your manuscript
accepted, getting your grants funded, or even getting your well-deserved
promotion.

This guide
is meant to give a short introduction to writing for chemistry students at
Oregon State. It is not a comprehensive writing
reference, and most likely will not address specific questions that arise. It will introduce
some major issues in writing about chemistry, and point you to some excellent
resources. Since chemistry students will spend most writing time
producing lab reports, that will be one focus of this guide.

Resources for help with writing

It
may seem obvious, but remember that your instructors are there to help. Did
they provide handouts or online information with specific instructions on
style, format, and a checklist of items
to include in the report? Since expectations will vary from class to class,
and sometimes even from report to report, it is important to understand what is
being requested before organizing your results and beginning to write. A
grading sheet specifying the number of points or relative weight given to each
part of the report can help you to focus your efforts. Find out if your instructor will provide
these in advance.

The ACS Style Guide, A Manual for Authors and Editors, 2nd ed. (Dodd, J., Ed.; American Chemical Society, Washington, DC, 1997) is an
excellent resource with writing tips
and detailed descriptions of the ACS writing conventions. This is also a
required text for the chemistry writing intensive (WIC) classes CH 462 and CH
463. We strongly suggest that you invest some money in this reference as soon as you
begin the integrated lab sequence. The guide can be ordered at http://www.oup-usa.org/j778/isbn/0841234620.html

The OSU Student Writing Center in 123 Waldo.
(tel. 737-5640; http://osu.orst.edu/dept/writing-center) provides free writing assistance to OSU
students. That could be the best deal on campus ! Their services include
one-on-one appointments to discuss your individual writing projects and
questions, an on-line form for submitting work in progress for
critical evaluation, and an e-mail address (WritingQ@mail.orst.edu)
where specific questions about sentence mechanics, punctuation,
documentation, and style are promptly answered.

General guidelines for writing reports

As
noted above, instructors differ in their expectations for lab reports. This is
reasonable when you consider that there is also a wide variation in the
requirements for different chemistry journals and publishers. Even so, a long experience in reading lab reports, papers,
and thesis drafts indicates that there are common areas of confusion for many
students, and therefore we provide a few general guidelines to help in creating reports or publications.

1. Use the correct verb tense

Lab reports and research papers should be mainly written in the present tense. You should limit the use of the past tense to (1) describing specific experimental methods and observations, and (2) citing results published in the past. The following sentences can be written in the past tense:

The solid was washed with water, then dried overnight in a dessicator.Jones et al found that polymers with absorption maxima between 200 and 300 nm degraded when exposed to ultraviolet radiation.[1]

Data
analyses, on the other hand, should be written in the present
tense:

Extrapolation of the line in
Figure 3a gives a polymer viscosity of 40.2 cp: an error estimate using eq. 2
provides an uncertainty of 0.4 cp.

2. Write in the third person

A
common question is whether the words I, me, my, we, our, or
us, belong in science writing. Because scientific experiments demonstrate facts that do not
depend on the observer, reports should avoid using the first and second person.
For
example, the second sentence below is better because it avoids the use of the
first person:

Stirring
the solution for 2 h, and subsequent filtration, yielded a yellow powder.

However,
when referring to your own results or conclusions, it can be simpler and
clearer to use the first or second person:

While Smith and
Jones report a cell dimension, c, of 23.3(1)Å, the authors' own data indicate a
value of 23.6(1) Å.Smith and Jones report a cell
dimension, c, of 23.2(1) Å, but our data yield a value of 23.6(1) Å.

The authors' own data is an awkward phrase and "our data" in the
latter sentence is better.

3. Be clear but concise

Reports and papers should fully describe
experiments in a precise and factual manner.
Both the depth of the error analysis and the writing style must be appropriate to
this task. Consider the following sentence in a discussion:

The calorimeter vibrated a
little, but it is still easy to measure the peak in Figure 1 very accurately.

Words and phrases such as "a little", "easy", and "very
accurately" have no definite meaning, and are therefore inadequate.
Quantitative, or semi-quantitative, descriptions and analyses are always
preferred over the use of such imprecise terms. In the following rewrite, the error
is much more clearly described:

The largest source of error
is vibration, which is estimated at 1-5 W/kg RMS. This adds at most a 4%
uncertainty to the peak integration, and values obtained are therefore reported
as +- 4%.

Although
you should strive to describe experiments in sufficient detail to be
reproduced, it is also important to write concisely. Often, text can
shortened by condensing or rephrasing without decreasing the meaningful
content. In the two examples below, the latter conveys the same information in
a more concise, and preferred, writing style.

Distillation
fractions three and four were combined in a 100ml round-bottom flask. To this flask was added 1.966g (0.0114 mol)
of benzoic acid. The flask was then
connected to a long column, distilling head, and condenser. Glass-wool and foil was again wrapped around
the column and distilling head.In a 100 mL round bottom flask equipped
with a water jacketed condenser and wrapped column and head, 1.966 g (0.0114
mol) of benzoic acid was added to the combined third and fourth fractions.

4. Revise
and proofread

Treat your first
written copy as a draft, and then
read through and revise. In WIC courses, some assignments will have revision
steps included in the submission and grading process. Many students are surprised
at how many simple errors can be found in first drafts, and how much their writing improves after using this simple method. A final
proofreading is also important, and can help to minimize spelling and
typographical errors. A few minor errors are almost inevitable in any written
document, but reviewers, and instructors, can usually tell when they are reading
a first draft. Along with a "human" proofread, use a spell check routine to help
spot errors.

Presenting data...the good, the bad, and the
ugly

Reports
should usually include a narrative text that describes and explains the information
presented. Use the results section to explain the purpose of every figure,
schemes, equation and table. Published research results never include "orphan" data, that is, information that is not explained or put into context by the
written text. This is also a good rule
to follow in lab reports.

When
referring to a figure, table, or equation, use its number in the text, for
example:

A
plateau was observed at reduced pressures greater than 0.1, as indicated in
Table 1.

It follows that
every figure, table and equation needs a number. Figures and tables require a
caption that includes the number and a descriptive title:

Figure
1. Mass uptake vs. reduced pressure for
Zeolite 5A.

Table
1. Powder Diffraction Data Obtained for
Zeolite 5A.

Note that the labels "chart" and "graph" are somewhat antiquated terms, and have
been largely replaced by "figure". Equations will normally have a number placed
in parentheses at the right margin:

E = mc2

1

Here
are some additional tips for preparing figures and tables:

All graph axes require labels that include both the variable
name and units.

Axes should use reasonable scales to clearly show the data and
have labeled tic marks. The axis labels do not need to show the full number of
significant figures.

Table columns should specify the units employed under each
heading.

Table entries do generally need to indicate the appropriate
number of significant figures (you may need to adjust the spreadsheet column formats appropriately).

Below
are some examples of good (on the left side) and bad (on the right) tables and
figures. How many problems can you find with those on the right side ?

Standard formats

Instructors
(and editors) can be picky about writing conventions. Literature citations,
symbols, and abbreviations all require strict adherence to a standard format.
Unfortunately, the particular standard used varies between publishers. An
important standard is that adopted by the American Chemical Society (ACS), and
this will be used by many chemistry lab courses at OSU. It would be
quite difficult to memorize all the forms for literature citations alone.
Fortunately, there is no need to do so. The ACS Style Guide (see above) lists
all the required formats and provides easily-followed examples. Nevertheless,
it's useful to be familiar with the most common citation formats and abbreviations. Some
frequently-used ACS formats are provided below.

For
journal articles:

1. Bode, H.; Jenssen, H.; Bandte, F. Angew. Chem. 1953, 65, 30.

Note -"65" is in italics and
refers to the volume number, and "30" is the first page of the article.

Writing Ethics

In
the sciences, results are usually discussed in relation to the work of others. Your
writing will therefore often refer to results or conclusions that are not your
own. This is fine as long as you clearly distinguish between your results and
those obtained from other workers or the literature. Each time outside results are cited, a
reference must be provided to the original source.

A
related issue lies in the use of quotes from another work. The exact
duplication of text from an outside source is acceptable only if it is placed in
quotations and a reference provided. Paraphrasing or summarizing other results
can also be acceptable if a reference is provided. However, incorporating another author’s words or style into your
own writing is not allowed, even if the original work is referenced. A discussion of this issue and some useful examples of acceptable vs. unacceptable
use are provided in "Avoiding Plagiarism @ Oregon State University" at http://osu.orst.edu/admin/stucon/plag.htm

When
there are group assignments or reports, make certain that you understand the
instructor's expectations for shared vs. individual contributions. Students
often do experimental work in groups, and are encouraged to discuss the lab
results and data analyses
with others. However, report writing is
most often expected to be an individual effort.

Test your writing IQ

Here are
some links to online quizzes about writing. Each site has a large number of
quizzes with answers provided. Try some and see how you rate.

Some real examples

The following are all examples taken from
student reports in OSU chemistry. In each case, a revised version follows the
original text. For practice, read each original text, then compose a revised version before reading
the one provided.

1.

Original
text:

Distillation
fractions three and four were combined in a 100ml round-bottom flask. To this flask was added 1.966g (0.0114 mol)
of benzoic acid. The flask was then
connected to a long column, distilling head, and condenser. Glass-wool and foil was again wrapped around
the column and distilling head.

Revised
form:

In a 100 mL round bottom flask equipped
with a water jacketed condenser and wrapped column and head, 1.966 g (0.0114
mol) of benzoic acid were added to the combined third and fourth fractions.

2.

Original
text:

Next
the copper solution was prepared. This was done by weighing out 0.1821 g of
copper nitrate and diluting it in 10mL of tap water.

Revised
form:

A solution was prepared by
dissolving copper nitrate (0.1821 g) in tap water (10 mL).

3.

Original
text:

If for
example, we could have used a red and green apple to determine the components,
we could have averaged the data and obtained more accurate results.

Revised
form:

If, for example, data were
obtained from both a red and a green apple, the averaged results could provide
more representative values.

4.

Original
text:

This
experiment intends to investigate upon any measurable amounts of Nickel in the
surrounding mud area and within barnacles living on the pilings.

Revised
form:

The purpose of this experiment is
to determine the nickel content in the surrounding mud area and in the
barnacles living on the pilings.

5.

Original
text:

For
the final yield of pentene isomers, only the elimination sample was
considered. . . The yields are reported in Table 2-3.

Revised
form:

The calculated final yields of
pentene isomers (Tables 2 and 3) are based on the elimination step only.

6.

Original
text:

The
contents of the flask were poured into a separatory funnel, and mixed with
increasing vigor. The evolving gas was
vented periodically. The product was
allowed to separate into two distinct layers. The bottom, aqueous, layer was bright yellow. The top, ether, layer was reddish-brown and transparent.Each layer was decanted into separate
containers.

Revised
form:

The product was transferred to a 1
L separatory funnel and upon mixing separated into a bright yellow solution
(bottom layer) and a clear ethereal reddish-brown layer with the evolution of
carbon dioxide.

7.

Original
text:

The
final solution was cooled using an acetone-ice bath. A temperature of -5 C was necessary to avoid the decomposition of
the diazonium salt. Hypophosphorous
acid and sodium nitrite were slowly added.

Revised
form:

To avoid the decomposition of the
diazonium salt, the resulting solution was cooled to -5 °C using an acetone-ice bath and then hypophosphorous acid
and sodium nitrite slowly added.

8.

Original
text:

The
contents of the flask were poured into a separatory funnel, and mixed with
increasing vigor. The evolving gas was
vented periodically. The product was
allowed to separate into two distinct layers. The bottom, aqueous, layer was bright yellow The top, ether, layer was reddish-brown and transparent. Each layer was decanted into separate
containers.

Revised
form:

The product was transferred to a 1
L separatory funnel and upon mixing separated into a bright yellow solution
(bottom layer) and a clear ethereal reddish-brown layer with the evolution of
carbon dioxide.

9.

Original
text:

The
first part of this experiment was to determine the percent removal of lead,
calcium, magnesium, and copper.We had
thought that there was not enough lead and copper left after we filtered the
tap water, so two spiked solutions were made.

Revised
form:

The purpose of the first part of
this experiment is to determine how effectively filtration removes lead,
calcium, magnesium, and copper from tap water. Although low levels of the metals were accurately detected in spiked
solutions, no detectable Pb or Cu was found in the filtered sample.

10.

Original
text:

This
should have given us a 5.00ppm solution instead the ICP data showed that we had
a 1.373(+/-0.0374)ppm. We decided that
we would use the ICP data for all our calculations.

Revised
form:

ICP data indicated that the
solution prepared to contain a Pb concentration of 5.00 ppm actually contained
1.373 +/- 0.037 ppm. The ICP values
were used in subsequent calculations.

11.

Original
text:

The
standard addition for the tonic water was done by using the tonic water solution
and doing a 1 to 10mL dilution on it with the sulfuric acid. A signal was obtained for the sample. After the first signal was taken 15μL
of 10ppm quinine sulfate stock was added, the signal was then taken.

Revised
form:

For the standard addition
measurement on tonic water, first a tonic water test solution was diluted 1 to
10 with sulfuric acid in a 10 mL volumetric. The absorbance was measured before
and after 15 μL of a 10 ppm quinine sulfate stock solution was added to
the cuvette.

12.

Original
text:

It was
observed that the barnacle sample was very well digested, but minute traces of
sludge were still found in the mud cell. Indications of this left over sludge may be from silicon waste left in
the sand and could not be further digested with the acid used. This silicon waste was found to be
negligible due to the belief that all of the existing Nickel on the silicon was
dissolved by the HNO3.

Revised
form:

The barnacle sample was very well
digested, but minute traces of particulates remained in the mud cell. These
particulates are assumed to be silica from sand since all other known
components dissolve in nitric acid.

13.

Original
text:

The
following standard concentrations were used to follow Beer’s law for the
absorbances at the corresponding wavelength:(Table)

Revised
form:

The standard concentrations were
measured at the corresponding wavelengths and the data provided in Table 1.

14.

Original
text:

Some
changes were made to this procedure with one of them being that the absorption
corresponding to the galactose was not found for both sample sets ...Another change is that the final
absorption readings were taken 20 minutes after adding the final enzyme,
β-galatose dehydrogenase, instead of 15 minutes.

Revised
form:

One change made to the written
procedure was that the absorbance due to galactose was not obtained for both
sample sets. .....A second change was that the final absorbance measurement was made at 20 min
instead of the suggested 15 min after adding β-galatose dehydrogenase.

15.

Original
text:

Twelve
penny solutions were analyzed using flame atomic absorption, and this data was
used to construct a calibration curve for each metal.

Revised
form:

The twelve solutions obtained by
dissolving pennies were analyzed using flame atomic absorption
spectrophotometry, and these data were used to construct a calibration curve
for each metal.